Antibacterial hand wash investigation

[Purple_Nurples_]

Hi, I'm new here and just looking for a wee bit of advice. I am currently planning an investigation on the effectiveness of antibacterial hand washes and not decided on how to go about it. I can either have people wash their hands and then place their fingertips on an agar plate and count colonies (if any), make bore holes in the agar and drop some of the hand wash in and then measure the clear zone or I can soak assay discs in the hand wash and place it on to an agar plate that has a culture of bacteria.What do you think would be the best?

Thank you

Edited May 1, 2012 by Purple_Nurples_

[CharonY]

For better reproducibility it is easier to measure zone of inhibition, or count live titer after a defined exposure of a given culture.

[ewmon]

It's probably been done a zillion times already, but you could test for the minimum inhibitory concentration (MIC) of various hand washes. If this is an academic project, then that's probably good enough, but if this is for work, you should also note that the alcohol-based washes, if used several times daily, day after day, will cause the skin to crack, thus exposing the body to germs. For example, medical personnel shouldn't use alcohol-based washes.